package com.opentool.web.spring;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
@Component
public class SpringUtil implements ApplicationContextAware {

    private static ApplicationContext applicationContext = null;
    // 非@import显式注入，@Component是必须的，且该类必须与main同包或子包
    // 若非同包或子包，则需手动import 注入，有没有@Component都一样
    // 可复制到Test同包测试

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        if(SpringUtil.applicationContext == null){
            SpringUtil.applicationContext  = applicationContext;
        }
    }

    //获取applicationContext
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }

    //通过name获取 Bean.
    public static Object getBean(String name){
        return getApplicationContext().getBean(name);

    }

    //通过class获取Bean.
    public static <T> T getBean(Class<T> clazz){
        try{
            T t=getApplicationContext().getBean(clazz);
            while (true){
                if(t==null){
                    t=getApplicationContext().getBean(clazz);
                }else{
                    break;
                }
            }
            return t;
        }catch (Exception e){

        }
        return null;
    }

    //通过name,以及Clazz返回指定的Bean
    public static <T> T getBean(String name,Class<T> clazz){
        return getApplicationContext().getBean(name, clazz);
    }

    /**
     * 同步等待获取Bean对象
     * @param clazz
     * @param <T>
     * @return
     */
    public static <T> T getBeanSync(Class<T> clazz){
        ApplicationContext context=getApplicationContext();
        while (context==null){
            context=getApplicationContext();
            break;
        }
        return context.getBean(clazz);
    }

}
